Most high performance tennis racquets today have frames made of a fiber-impregnated resin, particularly graphite. One shortcoming of graphite and other resin frames, however, is the tendency to develop small cracks when subjected to localized stress, which occurs if the frame is hit against a hard surface such as the ground. Once a crack forms, it tends to propogate each time the racquet hits the ball and eventually can cause the racquet to fail.
Damage is most likely to occur when returning a low shot, when the tip of the racquet is swung close to the ground. In order to protect against damage from accidental impact with the court surface, it is customary with graphite racquets to provide a plastic bumper strip over the tip region of the frame. The bumper strip has grommet pegs for the strings, so that it both acts as a bearing surface for the strings and covers the outside surface of the frame.
Recently, racquet manufacturers have introduced new graphite frames in which the cross-sectional height, i.e., the dimension perpendicular to the stringing plane, is enlarged in selected parts of the head or throat region, to produce a desired frame performance. An example of such a racquet is the Prince CTS, which is disclosed in commonly owned U.S. patent application Ser. No. 178,255, filed Apr. 6, 1988 and in which the height of the frame increases linearly from the top of grip to the racquet tip. While the geometries and resulting performance benefits of racquets offered by other companies differ, such racquets have come to be known generally as "wide body" tennis racquets. The outside surface of such racquets may be provided in the customary manner with bumper strip along the outer tip region.